Other intangible assets with definite lives (Details) - USD ($)	3 Months Ended		9 Months Ended
	Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2017	Oct. 31, 2016	Jan. 31, 2017
Indefinite-Lived Intangible Assets (Excluding Goodwill) [Abstract]
Finite-Lived Intangible Assets, Amortization Method			Patents are capitalized and amortized on a straight-line basis over a period not to exceed the legal lives of the patents.
Finite Lived Intangible Assets, Intent or Ability to Renew or Extend Arrangement			The Company expenses costs incurred to renew or extend the term of intangible assets
Gross patents	$ 2,640,000		$ 2,640,000
Accumulated amortization	2,410,000		2,410,000		$ 2,380,000
Amortization expense, next twelve months	45,600		45,600
Amortization expense, year two	37,500		37,500
Amortization expense, year three	34,700		34,700
Amortization expense, year four	28,100		28,100
Amortization expense, year five	17,400		17,400
Amortization expense, thereafter	93,800		93,800
Patent amortization expense	$ 12,000	$ 12,000	$ 34,000	$ 34,000